AVR-Chat

Hi,
  The bootloader code needs to be assembled and loaded into the m8 via a 
"conventional programmer". The STK500 is fine.

       AFTER that, application code is loaded into mega8 via the bootloader 
code and the uart interface using the progwin.exe program connected to the 
target avr's uart interface directly (add max232 or other rs232 level 
translator as required).

   Some notes:
  The fuses have to be set properly.
  The boot loader code looks for an <esc> char in the first couple of 
seconds to enter program mode,
     else it vectors to the regular reset int.
  Be sure to use the most recent version of progwin for mega8 support.
  Pay attention to xtal freq. and baud rates

    This is just one quick way to get a bootloader going. As David 
recommended, you really should read the app notes and data sheets to 
understand what is going on. Then you can make a bootloader that meets your 
particular needs. The assembler code is a good resource to see how other 
people are doing this and to perhaps see how the hardware has to be 
configured. I've gotten spoiled by avrfreaks.com site, but all the avr data 
sheets and app. notes are available from amel.com

regards,
-carl

At 10:39 AM 12/25/2004, you wrote:
>Hi Carl,
>
>Thank you for your short and helpful informations.
>
>I have one question:
>
>"After I download the bootloader, how can I download the Application Codes 
>without using STK500?"
>
>Do I need to write an window application software or can I still use 
>AVRProg.exe or AVRStudio.exe to download Application Codes after that 
>without using programmer?"
>
>Best Regards,
>Nay Oo
>
>Henry Carl Ott <carlott@interport.net> wrote:
>Normally I'd say try www.avrfreaks.com, but the site is down at the moment.
>   You can try the site in a couple of days and see if they can get back up.
>
>   I do have a modified atmel app note boot loader for the mega8 on my
>projects page.
>   <http://users.rcn.com/carlott/>http://users.rcn.com/carlott/
>
>   It's reasonably small, written in assembler, uses the atmel avrprog.exe
>program to download code.
>
>
>Hope that helps a little,
>
>-carl